Ammeter



1 1931. J. E.-ESHBAUGH 113051447 METER Filed April 19; 1929 J SSE- ESHBAUGH, QFil TJ1fiiGAm ssre deir 3 ABQ FB Ii-F I' or rLnv'r, menlerien rrpomrmrorMrenregrry: s

to improvementsin ammetersf p 1 A 5 In .ammeters in u v e todey, where u the p manent-biasing magnet is positioned closely "adjacent the conductor, 1t hes heen foundff that. thelines of force of the conductor tend to demagnetize or de-energize the'permaneiit; magnet andthelfeby interfere with the proper s o operation 'o'fthe'ammeter; It isenwobj'eothf V the invention to proiiide niezins whichfwill prevent the demagnetization of" the erm-f v .The pifice of'softs'rong Lhfch serges' tq centrate thejmegnetic -11 nes-;.of 'Efiorce is} prefj:

v, v erabl'y prouided with.enlergedtends which are a 5:3 positioned direetlyet the, poles ofthemagnet 1" ."in order to pullawey; from theflmagnet. the lines o fvforce of the conductor; fliheso ftiron l pieoe therefore serves to; the lines) of u force-by providing 'an iron pathins' teadofthe; 3e usual air path, f i The inyentionelso ,aimsto prov de aphrrality oftongues on the instrument :casiiigto; position the insulating strip on which the r frame and conductor of the instrumentfla-re 5 mounted; andto provid'efa means for Holding the securing bolts in place, and 'at 'theisame time preventingtilting of the frame Whenjthe bolts are applied; This latter is accomplished by providing the fe'et ofthe conductor freme J I v a j fl flanges which are positioned ii Lni j plene".

' transverse tof-theiaplane ,of;.,ltl1e,le'gs of the frame; Asthe holtsare applied the heads will strike againstthe'flanges and p" V Ventth'e tiltingofth'e frame. Onthe drawingszf 1 ,1

" Fig, 1 isa front viewrofjanainmeter with!v the'dial removed and parts broken awayrandi shown in section for purposeso'f clearer i1111stration.- r

e, mm

A iic tion'reed:Arum119,1 i This invention relates to: electrical 111g lnstruments and haspart cular reference,

t. l wer [no tilting of the frame; 1

1929 Serial message." i

Fig

fluxiconcentrating pieeeg v is a persp'eetiveyiew of the 'conduo tor frame and the meohanism of theammete'r. 3 {Fig.{lis a detail .v'i wof themeans for-pos i-f... tioning theinLSXiIating material'on the casing-t Fi -J? t Yrer e ive V e of the sq'ftironi igsJfiZandifflareI'planiand side iews oi a; modification;

flux concentrator, and permanent magnet showing the concentrationof the lines offoree of thejool ductor ewayrirom the magnet. i if n to th re i S 2 indicates h oase oi ag er IWhioh-isto suitably position iatingmeterial lO. 1 By referring to d d jon one1si'de,yyhile the twotongues} ontheslopposite side of the -,PP insulation"1p Onthefinsjulation lO; :thereare positioned .1? is "egperspectiveiVieW of the flux ajmodifi ed ofi iiux"eoncentratingmeans; i (Fig. 10; s a sectlon throughthe conductor, 7

I A case is provided at its bottom ithuthe integraltongues 4, 6 and i i ll bel notedftliehfbut one tongue 7 thefeet '12 :of the eondfubtor'frame 14. I The J ings to allowfl for the passage of the terminal bolt s l8.: Each. terminal bolt has the head -feetzarep roiiid ed with the flanges 16 on their inner -sides "and; (likewise with suitable open- I eo'gprdvidedl iith afflat 22 which is adapted I to ebut'egain ft oi'.conformrt the flange as shown in Figs; land fi. Thi'sis'tructure is an improvement over prior devices inthat when the;-belts.';18 are rigidly applied to hold the feetin placei'the flats '22 and flanges 16 will;

tend slightlyto hendithe legs '24s toward each;

has "been f founi to :be very objectionable;

othergor teiid to push {the flanges 16 slightly; inwardly If the ZOfwere shifted through 9D .dgreesfso astopressagainst either. the;

With theoonstri otion as shown there Will be The f'nte'grel conductor 14 "includes the 7 2 I W v 1,805,447

bridge is provided with the tongues or ears 30,

- 32, 34, 36 and 38, all of which are upwardly bent away from the conductor. g cars 36 and 38 are provided with openings Two of the adapted to receive rivets 40 which secure the dial 42 in place.

' Received between the ears 38 inclusive isthe permanent magnet 44. By referring to Figspl, 2 and 3,it will be apparent that.

the earshold the magnet against transverse movement in all directions. Positioned between the magnet 44 and the bridge 28of the conductor is the flux concena trating member or soft iron piece 46. Thls 1 'member is better shown in the perspective view in Fig. 5. The member comprises the enlarged end pieces 48 and the connecting" arms 50. At itsmid-portion it is provided with an enlarged portion 52 having the'prongs 54 by means of which itis secured to the conductor bridge 28. An opening 56 is provided at itscenter for a purpose which will 1 be later described.

By referring to Fig. 10 it will be seenthat as the lines of force of the conductor pass be- I tween magnet and conductor the function of the enlarged ends 48 will be to concentrate the flux lines so as to divert them away from the magnet 44. The enlarged ends 48 therefore act as ashunt for the magneticlines of force and prevent them from exerting theirinfluence on the permanent magnet 44 which I "removes therefrom the tendency towarddeen- 'ergization or de-magnetlzation.

The bridge 28is provided withtlie 6" iiin 58 and with the arm 60 at one side tliereo the arm 60 is'suitably bent so as to underlapt' The opening 58 is for the purpose of receiving the tongue 54 of the soft iron piece 46, while the bridgeand serve as amounting for the shaft 62 which has attached thereto the armature 64 and the pointer 66, held in place by means of thecollars25.

Both the end of the arm as well as the central portion of the bridge 28 are provided withdepressed portions 68 and 70 which are adapted to receive the pointed ends of the shaft 62. The

depressed portion-70 is received in the opening-56 in the flux concentrator 46.

By referring to Figs..6 and 7 it will b I noted that a modification of the invention is provided. The essential difference in this" be species resides in the provision in the conductor ofa recess or depressed portion 8Ov which'is adapted to receive the magnet '44" and the flu'x concentrator 46. The flux concentrator is shown in Fig. 8 and is essentially the same as that shown in Fig. 3, ex-

cept that it has but two prongs or tongues .54 instead of three shown in Fig. 5. Both theflux concentrator 46 and the magnet 44 are mounted in thedepression so as to leave the magnet substantially fiush with the 4 top thereof. This construction results in the elimination of the ears 30,38 inclusive. The

dial 42 is mounted by means of therivets 40 directly on the bridge 28'. The central part of the bridge 28 is provided with a pair of cut-outs 81, 83 and each prong 54 is received in one of the cut-outs.

By referring to Figs. 9 and 10'it will be seen that a modified form'of flux concentrator is'provided. In these figures the flux concentrators are formed of end caps having suitable bendable flange portions 92 and 94 which extend about the permanent magnet 44. The pieces 90 are shown as separated in Fig. 9, but if desired they may be united by means of connections similar to that shown at 50 in Figs. 5 and 8 and the flux concen trator slippedonto themagnet by allowing. one'of the flanges 90 to remain unbent un til the concentrator is placed on the magnet. The operation of the flux concentrators of Fig. 9 is the samev as that of Figs. 2 and 6.

In the species of 6 and 7 the arm' 60' is bent from the side of the frame opposite that cram species of Fig. 3 and is provided with a suitable opening to allow for the passage and swing of the pointer 66.

I claim:

-1. In an electric measuring instrument, a

conductor, a magnet secured tothe conductor, and a 7 soft iron member positioned between the conductor and'the polar areas of the magnet "to concentrate the lines of force of the conductor to reducethe" effects of demagnetization' onthe magnet. 2. In an electric measuring instrument, a

conductor, a magnet secured to the conductor, andmeans comprising magnetic mate rial having enlarged ends mterposedbetween said conductor and magnet to concentrate thelines of force of the conductor to reduce the effects of demagnetization on the magnet; w 53. In. an electric measuring instrumenha conductor, a magnet secured closely adjacent the condu'ctor, and an iron member secured adjacent the conductor in extension over the polar area of the magnet for concentrating the lines of force of the conductor to reduce the effects of demagnetizationon the magnet;

4.-In an electric measuring instrument. a

conductor, a magnet, and a soft iron memcent the conductor and magnetto concentrate the lines of force of the conductor to reduce rflha'ving enlarged ends positioned adja and means in the depression to concentrate the lines of force of the conductorto decrease the eflects of demagnetization on the magnet. I i 7 In an electric measuring instrument, a conductor, a depressed portion on said portion, vand a piece of iron betweensai conductor and magnet for concentrating the] lines of force of the conductor to reduce the effects of demagnetization on the, magnet. 8. In an electricineasuring instrument, a conductor, a depressed portion on said con} 7 conductor and magnet, said'piecei'of iron having enlarged "ends'adjacent the poles'of'; the magnet for concentrating the lines of force of the conductor to reduce the effects of demagnetization on the magnet.

9. In; an electric measuringflinstrument, a; i-

- conductor, a magnet rigidly held on'saidcon- V ductor, and a piece OflI'OIl between said con-'- ductor andjmagnet to vconoentrate'the lines, 7

of force of the conductor to reduce the effect of demagnetization of the magnet, said 7 piece of ironhaving enlarged ends at the portion-by means of WhlChiit is secured to the conductor. p p a 10. In an electric measuring instrumentya conductor, a magnet positioned onethe conconductor, a magnet seatedin said depressed V ductor a magnet seated in said depressedx jportion, and a piece oflro'njbetween said of the frame whenthe bolts are applied;

7 14. In an electric measuring instrument, a

conductor, a pointer having an. armature'rigidly mountedrelative thereto and subject to the field of the conductor, a magnet'mounted adjacent the conductor, and apiece of iron lane of thelegs wherebv toprevent tilting 7 ha-vingaportion to concentrate the magnetic flux of the conductor forthe'armature and other "portions to concentrate the conductors V linesof force at the ends ofthe: magnet to prevent demagnetization of the magnet.

: Intestimony whereof I aflix my signature JESSE ESHBAUGH.

poles of the magnet and fingers at its mid '7 V ductor,'and a piece of iron between said coni h, duct'or and magnet toconcentrate the lines" of force of the conductor to reduce;the=ef5 fects of demagnetization on the magnet, said conductor having an opening and saidpiece:

sition said insulatingfmaterial, and means to secure the frame and insulating material;

to the casing.

12. In an electric measuring instrument,a v a casing, a supporting frame 111 sald casmg, in? v f sulatingmaterial betweenthe frame'and casing, aplurality of tongues pressed from said 3 casing and engagingsaid insulation on one side thereof, a single tongue pressed from said casing-and engaging said insulation on the other side, said tonguespositioning said insulation 1n sald casing, and means to secure said frame and insulation to said cas-,

a mg. t J a 13. In an electric measurlng instrument, a j

casing, a frame insaid casing, feet onsa id fran1e,- legs integral with said feet,; bolts. to

secure said feet to'isaid casing a flat 'onthe headof each bolt, and/a flange on eachifoot against which the flat'abuts topreventrelative rotation of the bolts and frame, said i flange positioned in a'plane intersecting the it V 'iao 

